The United States, under President Barack Obama, may well be unable to stop Iran from obtaining nuclear weapons, former Republican presidential candidate Sen. John McCain tells Newsmax TV.

“Do the Iranians really think we’re serious?” the Arizona senator, the ranking GOP member of the Senate Armed Services Committee, asks Newsmax in an exclusive interview. “They watched us leave Iraq in disarray. They’ve watched us stand by in Syria — and they know we’re leaving Afghanistan.

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“We watch the North Koreans continue to test nuclear weapons and threaten us.”

McCain said former U.S. Secretary of State and Nobel laureate Henry Kissinger was right in warning over the weekend that the United States and Israel were very close to a nuclear crisis with Iran.

“There has emerged in the region, the current and most urgent issue of nuclear proliferation,” Kissinger, 89, told the World Economic Forum in Davos, Switzerland. “For 15 years, the permanent members of the United Nations Security Council have declared that a nuclear Iran is unacceptable, but it has been approaching.

“In a few years, people will have to come to a determination of how to react, or the consequences of non-reaction,” Kissinger added. “I believe this point will be reached in a very foreseeable future.”

“I have no doubt that countries in the region are certainly not sure whether we are going to be effective in preventing Iran from acquiring the nuclear weapons,” McCain told Newsmax. “The centrifuges continue to spin — and it’s a very, very serious situation.”

Editor's Note: Read the Full Newsmax Interview With John McCain Below.